SYNCHRONIZATION OF NANOMECHANICAL OSCILLATORS

• US 20140176203A1
• Filed: 10/25/2013
• Published: 06/26/2014
• Est. Priority Date: 10/26/2012
• Status: Active Grant

• Current Assignee: California Institute of Technology
• Original Assignee: California Institute of Technology
• Inventors: Roukes, Michael L., Villanueva Torrijo, Luis Guillermo, MATHENY, Matthew, Cross, Michael C., Karabalin, Rassul
• Granted Patent: US 9,660,654 B2
• Time in Patent Office: Days
• US Class Current: 327/146
• CPC Class Codes: G01N 29/11 by measuring attenuation of acoustic waves
• CPC Class Codes: H03B 5/30 with frequency-determining element being electromechanical resonator
• CPC Class Codes: H03L 7/00 Automatic control of frequency or phase; Synchronisation

Abstract

Synchronization of oscillators based on anharmonic nanoelectromechanical resonators. Experimental implimentation allows for unprecedented observation and control of parameters governing the dynamics of synchronization. Close quantitative agreement is found between experimental data and theory describing reactively coupled Duffing resonators with fully saturated feedback gain. In the synchonized state, a significant reduction in the phase noise of the oscillators is demonstrated, which is key for applications such as sensors and clocks. Oscillator networks constructed from nanomechanical resonators form an important laboratory to commercialize and study synchronization—given their high-quality factors, small footprint, and ease of co-integration with modern electronic signal processing technologies. Networks can be made including one-, two-, and three-dimensional networks. Triangular and square lattices can be made.

Claims

1. A device to provide synchronized oscillators comprising:

a plurality of nanoelectromechanical resonators adapted to function as oscillators, each oscillator comprising an input port, an output port, and a port to control device resonance frequency;

electronic circuitry electronically coupled to the oscillators and adapted so that the oscillators are synchronized with use of electronic feedback, wherein a signal from each oscillator is split into two different feedback loops.

2. The device of claim 1, wherein one of the two different feedback loops is an oscillator loop, and the other is a coupling loop.

3. The device of claim 1, wherein one of the two different feedback loops is an oscillator loop, and the other is a coupling loop, wherein, for each oscillator, the coupling loop of the oscillator is coupled to the coupling loop of at least one other oscillator.

4. The device of claim 1, wherein one of the two different feedback loops is an oscillator loop, and the other is a coupling loop, wherein the coupling loop of at least one oscillator is inductively coupled to the coupling loop of at least one other oscillator.

5. The device of claim 1, wherein one of the two different feedback loops is an oscillator loop which is dissipative, and the other is a coupling loop which is reactive.

6. The device of claim 1, wherein one of the two different feedback loops is an oscillator loop which is dissipative, and the other is a coupling loop which is reactive, wherein, for each oscillator, the oscillator loop is adapted to produce a nonlinear feedback signal in response to an oscillation amplitude signal;

and the coupling loop is configured to produce signal that depends substantially linearly on a frequency detuning of the oscillator from at least one other coupled oscillator

7. The device of claim 1, wherein one of the two different feedback loops is an oscillator loop, and the other is a coupling loop, wherein in the oscillator loop a signal is amplified with gain g and then sent through a saturating limiter.

8. The device of claim 1, wherein one of the two different feedback loops is an oscillator loop, and in the oscillator loop a signal is amplified with gain g and then sent through a saturating limiter.

9. The device of claim 1, wherein one of the two different feedback loops is an oscillator loop, and in the oscillator loop a signal is amplified with gain g and then sent through a saturating limiter and then to a voltage controlled attenuator after each limiter which sets a level of oscillation.

10. The device of claim 1, wherein one of the two different feedback loops for each oscillator is a coupling loop and comprises a common loop common to the two oscillators, wherein a signal is amplified so that a voltage controlled attenuator adjusts the signal level in the common loop, thereby setting the coupling strength.

11. The device of claim 1, wherein a frequency difference is controlled by adjusting the stress induced in one of the resonators by a piezovoltage.

12. The device of claim 1, wherein the device provides for three parameter controls (Δ

ω

, α

, β

) which are independent, wherein Δ

ω

is the difference between resonant frequencies of the resonators, α

is the amount of frequency pulling, and β

is the coupling strength.

13. The device of claim 1, wherein the device provides for three parameter controls (Δ

ω

, α

, β

) which are controlled by independent and external DC voltage sources, wherein Δ

ω

is the difference between resonant frequencies of the resonators, α

is the amount of frequency pulling, and β

is the coupling strength.

14. The device of claim 1, wherein the oscillators are coupled in a one-dimensional chain.

15. The device of claim 1, wherein the oscillators are part of a multidimensional network.

16. The device of claim 1, wherein the oscillators are part of a two-dimensional network.

17. The device of claim 1, wherein the oscillators are part of a three-dimensional network.

18. The device of claim 1, wherein the oscillators are part of a random network.

19. The device of claim 1, wherein each oscillator is equally coupled to all other oscillators.

20. The device of claim 1, wherein the oscillators are coupled through a transmission line.

21. The device of claim 1, further comprising a coupling bus adapted to provide selectable coupling of the oscillators.

22. The device of claim 1, further comprising a coupling bus adapted to provide selectable coupling of the oscillators, wherein the selectable coupling is at least one of all-to-all coupling, nearest-neighbor coupling, or decaying coupling.

23. The device of claim 1, wherein some but not all of the oscillators are coupled.

24. The device of claim 1, wherein at least one attenuator is used between oscillators.

25. The device of claim 1, wherein the oscillators form part of an oscillator lattice.

26. The device of claim 1, wherein the oscillators form part of a triangular lattice.

27. The device of claim 1, wherein the oscillators form part of a hexagonal lattice.

28. The device of claim 1, wherein the oscillators form part of a square lattice.

29. The device of claim 1, wherein the device comprises two to 99 oscillators.

30. The device of claim 1, wherein the device comprises at least 100 oscillators.

31. The device of claim 1, wherein the device comprises at least 10,000 oscillators.

32. The device of claim 1, wherein the oscillators are part of a random network.

33. The device of claim 1, wherein the control of device resonance frequency is adapted to be carried out by modifying stress, by piezoelectric or thermal methods, or through a capacitive gate.

34. The device of claim 1, wherein the device is a frequency source.

35. The device of claim 1, wherein the device comprises a sensor.

36. The device of claim 1, wherein the device comprises an amplifier.

37. The device of claim 1, wherein the device comprises a neural network.

38. A method of using the device of claim 1, wherein the oscillators are used in a synchronized state.

39. The method of claim 38, further comprising:

synchronizing the oscillators;

applying a stimulus to the oscillators that modifies the oscillation of the oscillators;

combining output signals from the oscillators to generate a combined output signal indicative of the stimulus; and

outputting the combined output signal.

40. A device to provide synchronized oscillators comprising:

a plurality of nanoelectromechanical resonators adapted to function as a plurality of oscillators, each oscillator comprising an input port and an output port;

electronic circuitry electronically coupled to the oscillators and adapted to synchronize the plurality of oscillators by;

controlling an anharmonicity of each of the plurality of oscillators; and

controlling coupling between the plurality of oscillators.

41. The device of claim 40, wherein the electronic circuitry comprises, for each of the plurality of oscillators:

an oscillator feedback loop configured to receive a signal from the output port and feed back a modified signal to the input port to adjust an anharmonicity of the oscillator.

42. The device of claim 41, wherein the electronic circuitry comprises, for at least one pair of a first oscillator and a second oscillator from the plurality of oscillators:

a coupling feedback loop configured to;

receive an output signal from the output ports of the first and the second oscillator,

feed back a modified signal to the input port of the first oscillator based on the output signals from the first oscillator and the second oscillator to control a coupling between the first oscillator and the second oscillator.

43. The device of claim 42, wherein the coupling feedback loop determines a frequency detuning between the first and second oscillators and the modified signal depends substantially linearly on the detuning.

44. The device of claim 43, wherein the coupling feedback loop is substantially non-dissipative.

45. The device of claim 42, wherein:

each of the plurality of resonators is mounted on an individual oscillator circuit board;

the electronic circuitry comprises a coupling bus separate from but in electrical communication with each of the oscillator circuit boards and is adapted to provide coupling between the oscillators.

46. The device of claim 40, wherein the electronic circuitry is adapted to synchronize the oscillators to substantially a single common frequency.

47. The device of claim 42, wherein each of the plurality of oscillators comprises a control port adapted to receive a signal for tuning the uncoupled resonant frequency of the oscillator.

48. A device to provide synchronized oscillators comprising:

a plurality of coupled nanoelectromechanical resonators adapted to function as oscillators, each oscillator comprising at least one input coupling port, at least one output coupling port, and optionally at least one port to control device resonance frequency; and

electronic circuitry coupled to the oscillators and adapted so that the oscillators are synchronized with the use of electronic control provided in a common coupling loop that couples respective output coupling ports and input coupling ports of adjacent ones of the oscillators.